1. Field of the Invention
This invention relates to a hinged device for doors of an aircraft nacelle as well as an aircraft nacelle that is equipped with said hinged device.
2. Description of the Related Art
The aircraft engines are generally integrated inside a structure, called nacelle below, connected by connecting means to the aircraft, in particular by a mast to the wing.
This nacelle has several functions, in particular those to regulate and to control the movements of the air around and in the engine so as to optimize the aerodynamic flow, to protect the engine from the outside elements, to minimize noise pollution, to ventilate the internal zones, to participate in the dispersion of mechanical stresses of the engine, and optionally to support the thrust reverser systems.
Finally, the nacelle is to allow the daily maintenance and the maintenance of the engine and its components.
For this purpose, the nacelle comprises, at its outside surface, an opening that allows access to the inside of the nacelle and a moving part that can occupy at least two positions, a first so-called closed position in which said moving part is located in the extension of the outside surface of the nacelle so as to block said opening, and a second position in which it at least in part releases the opening. For the remainder of the description, the moving part is called a door.
In FIGS. 1 and 2, a nacelle that is connected by a mast 12 to a wing 14 is shown at 10, whereby said nacelle comprises an air input 16 at the front and a lateral fuselage 18 with a longitudinal axis 20. The nacelle 10 comprises at least one opening 22, preferably two openings located on each side, on both sides of the mast 12, each able to be blocked respectively by a door 24.
According to the prior art, each door 24 is hinged relative to the upper edge of the opening 22 and pivots around an axis 26 that is essentially parallel to the axis 20 of the nacelle, located close to the mast 12.
In addition, locking means are provided to keep the doors 24 closed. According to an embodiment, the lower ends of the doors are connected when the latter are in a position that is closed by locks (not shown).
Advantageously, as illustrated in FIG. 2, two stands 28 are provided to keep each door in the open position.
Even if this type of door is relatively simple and allows easy access to the elements that are mounted in the low part of the engine, it does not provide full satisfaction for the following reasons:
The positioning of the door in the open position facing the opening at the median part and the top part does not promote access to these parts. Thus, the operators should slide between the door and the engine by first bending down to pass under the panel of the door by taking the risk of being injured by hitting the edges of the door.
In addition, this opening method does not make it possible to ensure optimum safety of the operators. Actually, even if they are held by stands, the doors can suddenly close again, due in particular to wind gusts, and can injure the operator located between the door and the engine.
As illustrated in FIG. 1, the upper parts of the existing hinged doors have significant wind pickup although the structures of the doors are sized to resist wind gusts on the order of 100 Km/h. In fact, these constraints in the open position are much more important than those to which the doors in the closed position are subjected. Thus, the doors are sized for rare cases of use.
Finally, for a door of large dimensions, its handling operation may prove difficult, whereby the operator may have to lift said doors to produce the opening. Beyond certain dimensions, it is necessary to provide an onboard system to assist in opening and closing, complicating the design and increasing the weight installed on the aircraft.
In addition, certain units of propulsion systems, of large dimensions in particular, can be relatively close to other parts of the aircraft, with configurations that can generate interferences between the door in the open position and the wing or the leading edge slat in deployed position, or any other fixed or mobile surface. It is necessary in these cases to install protections that also add additional weight to the aircraft.